1. Technical Field
The present invention relates to a non-volatile memory device and an electronic apparatus.
2. Related Art
High reliability is demanded for electronic apparatus mounted on a vehicle, an airplane, a ship, a train, or the like in which safety is required. Such an electronic apparatus may include plural non-volatile memory devices that store the same data (or data in which 0 and 1 are inverted). The data is, for example, several tens of bits of data for adjusting an analog circuit (hereinafter, adjustment data). In this case, it is possible to increase the data reliability by a mutual collation overall bits of data from different non-volatile memory devices when the data is read.
Then, if there is a mismatch of data, for example, it is possible to respond appropriately by providing a failure diagnosis function such as outputting a failure diagnosis signal. For example, JP-A-2006-18341 discloses an accurate failure diagnosis function which performs a double check based on a calculated checksum for each area.
However, along with an increase of non-volatile memory device capacity, if handling data increases (for example, hundreds of bits), then the size of the circuit for collation all the data bits may increase. In addition, along with a high integration of the non-volatile memory device, it is possible to integrate a combined capacity of plural non-volatile memory devices into a single non-volatile memory device. Therefore, it is demanded that a single chip non-volatile memory device have a failure diagnosis function and be capable of outputting data with high reliability.
In this case, by storing data in the plural memory blocks, it is possible to provide a plurality of data in which mutual collation is possible. However, in order to accurately diagnose a failure of each memory cell included in the memory block, it is necessary to first perform a failure diagnosis of a read circuit, called a sense amplifier. In the non-volatile memory device used in an electronic apparatus mounted on vehicles or the like, it is necessary to specify a failure area in the event of a failure. Therefore, it is necessary to perform diagnosis so as to distinguish between the failure of the sense amplifier and the failure of the memory cell.